Unless otherwise indicated herein, the materials described herein are not prior art to the claims in the present application and are not admitted to be prior art by inclusion in this section.
In some Echelle grating demuxes, input light with n (e.g., n=4 or other positive integer) different wavelength channels enters the demux through an input waveguide. From there, the light diffracts in a free-space propagation region and impinges on a grating that is on a Roland circle and has blazed angles. Light reflects from the grating leading to constructive interference for each of n input wavelengths (associated with the n wavelength channels) at n output waveguides, thereby spatially separating, or demultiplexing, the n wavelength channels from each other.
The subject matter claimed herein is not limited to implementations that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one example technology area where some implementations described herein may be practiced.